※ Material panel: the first piano key design effects. Pure imported 100% PC material (also known as bullet-proof plastic), high strength, good impact resistance, anti-aging ability, surface smooth and delicate, anti-ultraviolet radiation, not easy to fade, high temperature. At 100 ° C in the environment will not deform within 60 minutes, the ignition point above 850 degrees, leaving the external source will automatically extinguish the fire within 30 seconds. Switch contacts: contacts with silver-nickel alloy, durable, good conductivity, no pollution. Socket shrapnel: The 0.6 mm thick bronze (purple) refined, with corrosion resistance, wear resistance, high strength, elastic lasting, good conductive properties, not easy to fever, fatigue, and other characteristics. Terminals: The wiring plate holes for the wires without injury, large aperture easy wiring, which can take 1.5-4.0 mm wire. ※ making panels and base: the high cost of mold technology to produce precision wire walking is made, the panel no ripples, no shrink, smooth as a mirror, smooth and shiny base. Socket shrapnel: using highly automated metal forming machine tools, the overall is a copper pieces, corner flat, no riveting point, reducing the resistance of the material itself, reducing the situation rivet riveting part of the fracture and fever, and improve the safety performance of the product. Socket protection door: The door-round protection against electric shock, prevent unipolar insert to avoid the children poke plug electric shock. Lightning Waterproof: Waterproof additional lightning protection module, multi-layer protection, effectively reduce damage by lightning and overvoltage caused to persons and property.